A common but undesirable form of fellatio in which the teeth are used to scratch and bite the penis, due to either a lack of knowledge on how to perform the pleasure, or by accident. It is extremely painful and usually ends with the receiving partner telling the other member to immediately stop and leave.

John: So, how'd last night with that chick go?

Avi: It started out great, but right after she went down on me, I realized she had a terrible case of gingibitis, so I kicked her out of my room and finished the job myself.